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Published on: May 1, 2018
Universal scaling laws of diffusion: application to liquid metals
Alok Samanta1, Sk Musharaf Ali, Swapan K Ghosh
1Theoretical Chemistry Section, Bhabha Atomic Research Centre, Mumbai 400 085, India. alokk@apsara.barc.ernet.in
The Journal of Chemical Physics
|September 17, 2005
Summary
This study details a new universal scaling law connecting fluid diffusivity and excess entropy. This law accurately predicts liquid metal properties and offers a simpler calculation method than previous empirical approaches.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Materials Science
Background:
- Universal scaling laws are crucial for understanding fluid behavior.
- Existing empirical laws for diffusivity have limitations.
- Excess entropy and diffusivity are key properties in fluid mixtures.
Purpose of the Study:
- To derive and validate a new universal scaling law for diffusivity.
- To extend the applicability of this law to liquid metals.
- To compare the new law with existing empirical scaling laws.
Main Methods:
- Detailed derivation of the proposed diffusivity scaling law.
- Application of the scaling law to liquid metals (Rb and Cs).
- Comparison of calculated results with simulation data along the liquid-vapor coexistence curve.
Main Results:
- The new scaling law shows excellent agreement with simulation results for liquid Rb and Cs.
- The law is applicable across a wide range of temperatures and densities.
- The derived law is demonstrated to be superior to previous empirical models.
Conclusions:
- The new universal scaling law provides a robust framework for understanding diffusivity in fluids and liquid metals.
- This law simplifies the calculation of dynamical properties from equilibrium properties like the radial distribution function.
- The findings offer a more accurate and universally applicable approach compared to prior empirical methods.
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